Learn / FMK
Every FMK condition
299 diseases, deficiencies, toxicities and drug mechanisms harvested from every FMK deck — the ones sprinkled through a single bullet as much as the ones with their own slide. Pick what you're given and what you have to name, or let it cycle; distractors come from the same category so you have to discriminate (hypoketotic vs. ketotic hypoglycemia, which GSD, which urea-cycle enzyme…). Every answer shows the whole card with the lecture and slide.
Amino acid · FMK 07.1
Cystinuria Autosomal recessive
Defect / target: Defective COAL transporter (Cystine, Ornithine, Arginine, Lysine — dibasic amino acids + cystine) in intestine and renal proximal tubule
Mechanism: Failure to reabsorb cystine and dibasic amino acids lets poorly soluble cystine precipitate in urine as stones.
↑ Accumulates: Cystine, ornithine, arginine, lysine in urine
Presentation: Recurrent kidney stones; most common inherited amino acid transport disorder (~1 in 7,000)
Labs: Hexagonal crystals on urinalysis = cystine stones
COAL transporter; hexagonal crystals; a transporter defect — not an enzyme defect like homocystinuria
Learn the mechanism: Protein digestion & amino acid absorption →
FMK 07.1 Amino Acid Metabolism I · slide 7, 31, 32